onsemi NCP120BMX105TCG

Overview

NCP120BMX105TCG from onsemi is a 150 mA very low dropout (VLDO) CMOS voltage regulator with NMOS pass transistor and separate bias rail (VBIAS), delivering a fixed 1.05 V output at up to 150 mA with ±1.5% accuracy over −40°C to +85°C and ultra-low 75 mV dropout at full load - designed for noise-sensitive, space-constrained portable applications such as smartphone I/O rails and camera sensor power.

For engineers reviewing the NCP120BMX105TCG datasheet, pinout, applications, or equivalent options, key selection criteria include its dual-rail architecture (VIN/VBIAS), 80 µA typical bias current, logic-level enable control, stability with 1 µF ceramic output capacitor, and XDFN6 1.2 mm × 1.2 mm package thermal performance.

Technical Context

The NCP120BMX105TCG implements a dual-input NMOS-based VLDO architecture: VIN supplies the pass element while VBIAS powers internal control circuitry, enabling stable regulation even when VIN approaches VOUT. Its UVLO monitors VBIAS with 1.6 V threshold and 0.2 V hysteresis, ensuring reliable startup under varying bias conditions.

This variant lacks active output discharge (denoted by "B" suffix), distinguishing it from "A"-series parts. It features monotonic start-up, thermal shutdown at 160°C, and current limiting of 200–600 mA - all optimized for post-regulation in battery-powered systems where quiescent current and PCB area are critical.

Key Specifications

Pinout & Package

XDFN6 package (Case 711AT), 1.2 mm × 1.2 mm × 0.4 mm, with exposed thermal pad soldered to PCB ground plane for thermal management.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, dual-rail LDO applications.

Compared with XC6210B105MR-G and BD71840MWV, the NCP120BMX105TCG provides superior PSRR and lower dropout in a minimal 1.2 mm × 1.2 mm footprint - ideal for discrete, noise-critical post-regulation where bias rail isolation matters most.

Availability

NCP120BMX105TCG is available at Aetrix Electronics and suitable for smartphone I/O rails, camera sensor cores, tablet memory interfaces, portable DVR audio codecs, and other applications requiring stable component supply with tight voltage accuracy and ultra-low noise.

Supply support for NCP120BMX105TCG includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient technologies for automotive, industrial, cloud, medical, and IoT applications.

The NCP120 series targets portable electronics requiring ultra-low dropout, low-noise, and space-constrained power management - specifically engineered for post-regulation in battery-powered devices with dual-rail architecture needs.

FAQ

What is the output voltage tolerance of the NCP120BMX105TCG over temperature?

The NCP120BMX105TCG maintains ±1.5% output voltage accuracy across −40°C to +85°C junction temperature, with tighter ±0.5% accuracy at 25°C. This ensures reliable operation for precision I/O rails in smartphones and tablets where voltage drift could impact interface timing margins or logic thresholds.

Does the NCP120BMX105TCG require an external capacitor on the BIAS pin?

Yes, the NCP120BMX105TCG requires a minimum 0.1 µF ceramic capacitor between BIAS and GND, as specified in the datasheet's Application Information section. This stabilizes the internal control circuitry powered by VBIAS and prevents oscillation or erratic enable behavior under dynamic load conditions.

Can the NCP120BMX105TCG be used with a 1.0 V input supply?

No - the NCP120BMX105TCG requires VIN ≥ VOUT + VDO, and its minimum dropout is 37 mV (typical) at 150 mA. With a 1.05 V output, VIN must be ≥ ~1.087 V minimum; a 1.0 V input falls below this threshold and will cause regulation loss. The absolute minimum VIN is VOUT + 0.037 V under nominal conditions.

Is the thermal pad of the NCP120BMX105TCG electrically connected internally?

Yes, the exposed thermal pad on the NCP120BMX105TCG is internally connected to GND. It must be soldered to a PCB ground plane to ensure proper thermal dissipation and electrical reference - failure to do so degrades R_JA performance and risks thermal shutdown at currents above ~50 mA.

How does the NCP120BMX105TCG differ from the "A" version (e.g., NCP120AMX105TCG)?

The NCP120BMX105TCG lacks active output discharge functionality, unlike the "A" variant. When disabled, the "B" version leaves the output floating, while the "A" version pulls OUT to GND via an internal switch. This makes the "B" version suitable for systems where uncontrolled discharge could interfere with downstream circuitry or cause back-powering issues.